Oh I've got a couple books with recipes for making root beer. And of course the simplese way is simple syrup, carbonated wate, and root beer extract. But Cresswell's book is the only one that gives dates for some historic recipies for sodas. None of the historic root beer recipes in the book are dated to the war which is why I didn't bother mentioning them, but there are several that were in existence during the war. Didn't know of any re-enactors might be interested in that.

But there are also plenty of recipes that Cresswell put in that are more modern, including a couple for making your own root beer extract. He also has a version of dandelion wine he calls dadelion champagne because it's carbonated.